AUTOMATIC GAIN CONTROL APPARATUS OUTPUTTING NONLINEARLY VARYING CONTROL VALUE AND METHOD FOR OUTPUTTING GAIN CONTROL SIGNAL THEREOF

摘要

PURPOSE: An automatic gain control apparatus outputting a nonlinearly varying control value, and a method for outputting a gain control signal thereof are provided, which control a desired signal level within a short time, and thus perform accurate gain control. CONSTITUTION: An estimator estimates a level of an input signal. A subtracter calculates a difference value between the above level estimated by the above estimator and a reference value. And a gain controller(60) outputs a control value scaling the difference value which nonlinearly is output from the subtracter. The gain controller outputs the control value proportional to a square of the difference value.